518 TRANS OD/LU WIRING AND SWITCHES

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modart440

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guys just getting to wiring up my 518 swap with toggle switches. I have switched power going to the center pin on the trans connector is it normal to have 12 volts coming back on the overdrive and lockup wires with the key in the acc position?Also will you hear the OD solenoid click off/on without the vehicle running. This should be real simple but can't get my head around what I should and shouldn't see as far as conditions. My thoughts where switched 12v to center pin on trans front pin from trans(OD) to toggle other side of toggle to ground, rear pin on trans (LU) to other toggle switch and other side of this toggle to ground. Also does it matter if you use 2 or 3 position toggle switches?
Thanks mike
 
guys just getting to wiring up my 518 swap with toggle switches. I have switched power going to the center pin on the trans connector is it normal to have 12 volts coming back on the overdrive and lockup wires with the key in the acc position?Also will you hear the OD solenoid click off/on without the vehicle running. This should be real simple but can't get my head around what I should and shouldn't see as far as conditions. My thoughts where switched 12v to center pin on trans front pin from trans(OD) to toggle other side of toggle to ground, rear pin on trans (LU) to other toggle switch and other side of this toggle to ground. Also does it matter if you use 2 or 3 position toggle switches?
Thanks mike
The 12 volts I'm seeing on the 2 wires coming back from the trans plug OD/LU is this the way it should be? And the toggle going to ground completes the circuit ?
 
Subscribed. Headed this way too with an A500. Heres an archived schematic i have but I'm not sure its correct. Maybe others can chime in. Trailbeast has made a nice setup for this, theres also a company that makes a kit for the A518. Not sure why their kit wont work on my A500.

IMG_20190112_172632487.jpg


Screenshot_20191102-095144_Samsung Internet.jpg
 
Subscribed. Headed this way too with an A500. Heres an archived schematic i have but I'm not sure its correct. Maybe others can chime in. Trailbeast has made a nice setup for this, theres also a company that makes a kit for the A518. Not sure why their kit wont work on my A500.

View attachment 1715712283

View attachment 1715712284
Thanks but looking to do it with toggle switches
Thanks
Subscribed. Headed this way too with an A500. Heres an archived schematic i have but I'm not sure its correct. Maybe others can chime in. Trailbeast has made a nice setup for this, theres also a company that makes a kit for the A518. Not sure why their kit wont work on my A500.

View attachment 1715712283

View attachment 1715712284
ANYONE!!!!!!! How about all you transmission guys???Should you be able to hear the solenoid click when you flip the toggle switch???
Thanks
Thanks
 
Trailbeast did it with toggle switches, relays and pressure switches. Pic "is" of his shifter.

Screenshot_20191103-082337_Samsung Internet.jpg
 
I have had a good look at the various solutions to wiring the overdrive. I think I have come up with something new that solves the issue of switching in and out of overdrive around the speed of actuation. Others have used a time delay relay but this will allow instant switching.

Circuit for overdrive only. Lockup controlled by manifold pressure switch.

Overdrive wiring.jpg


The relay has 2 separate sets of contacts. There are 2 pressure switches. One determines speed (pressure) at which overdrive comes in. The other determines when it releases. When the transmission reaches the lower pressure the switch applies power to the higher pressure switch. Nothing happens. When the pressure increases enough to operate the higher pressure switch the relay operates and switches in the overdrive but it also bypasses the high pressure switch. The relay will then remain on until the pressure falls enough to switch off the lower pressure switch.

If adjustable switches such as those from PATC are used it will be possible to have a decent hysteresis with about 5lbs difference between on and off.

I can't try this out until the car comes back from having some metalwork done but I reckon it looks promising.
Please let me know what you think.
 
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